On the performance of physical layer security in virtual full-duplex non-orthogonal multiple access system

Weidong Guo,Yuxi Liu

doi:10.1186/s13638-021-02009-y

Abstract

This paper investigates physical layer security analysis of cooperative non-orthogonal multiple access (NOMA) communication system. A virtual full-duplex (VFD) relaying scheme with an untrusted amplify-and-forward (AF) half-duplex (HD) relay and a trusted decode-and-forward (DF) HD relay is used in this system to improve the spectral efficiency. In order to prevent the untrusted relay from eavesdropping, a simple and practical cooperative jamming scheme is designed to confuse the untrusted relay. The exact expressions of effective secrecy throughput (EST) for NOMA users and approximate expression of EST for non-NOMA user are derived. All theoretical results are validated by numerical simulations which demonstrate that the proposed VFD-NOMA scheme is superior to existing HD-NOMA scheme in cooperative system and jamming plays an important role for obtaining acceptable EST. In addition, simulation results shows that the best secrecy performance highly depends on the system parameters such as transmit powers and jamming signal power.

Highlights

As one of the promising key techniques of the fifth-generation (5G) wireless networks, non-orthogonal multiple access (NOMA) has been applied in various areas [1, 2]
According to the above references, this paper studies the cooperative virtual full-duplex (VFD)-NOMA transmission and investigated its secrecy performance with the presentence of an untrusted relay
The novelty of this study is that a novel cooperative jamming strategy is adopted to secure the untrusted relay VFD-NOMA networks and the effective secrecy throughput (EST) expressions are derived to obtain further insights into parameters on system performance, which shows that there exist the optimal values of source power, relay power and jamming power

Summary

Introduction

As one of the promising key techniques of the fifth-generation (5G) wireless networks, non-orthogonal multiple access (NOMA) has been applied in various areas [1, 2]. The novelty of this study is that a novel cooperative jamming strategy is adopted to secure the untrusted relay VFD-NOMA networks and the EST expressions are derived to obtain further insights into parameters on system performance, which shows that there exist the optimal values of source power, relay power and jamming power. These findings are of great theoretical value for practical secure communication. The SINR for p to decode its own message is given by γp→p

PRPE hEp hRE

YZ ρI

Conclusion